Nature of Operations and Basis of Presentation (Deferred Policy Acquisition Costs) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Recorded asset at beginning of period	$ 92,796
Recorded asset at end of period	95,891
Continuing and Discontinuing Operations
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Recorded asset at beginning of period	92,796
Underwriting costs deferred	55,314
Amortization of deferred policy acquisition costs	(52,219)
Recorded asset at end of period	$ 95,891

Amount of amortization expense (reversal of expense) for deferred policy acquisition costs.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Total amount of policy acquisition costs capitalized during the income statement period.

+ References

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- Definition

Amount, after accumulated amortization, of deferred policy acquisition costs and present value of future profits from insurance contract acquired in business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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